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Ischemic stroke is one of the most debilitating and deadliest conditions worldwide. Intravenous t-PA is the current standard treatment within 4 hours after onset of symptoms. Recent randomized controlled trials have demonstrated the efficacy of neurointerventional intra-arterial treatment in acute ischemic stroke. About 20% of acute ischemic stroke are classified as wake-up strokes, which falls out of the conventional treatment time window. New evidence suggests that some patients with longer time from symptom onset (up to 24 hours) may benefit from thrombectomy, probably in part due to variations in collateral circulation among individual patients. Advanced imaging can play a crucial role in identifying patients who could benefit from endovascular intervention presenting within extended treatment time windows. In this article, we review the advanced imaging algorithm for ischemic stroke workup in the multiple studies published to date and summarize the results of the clinical trials for late ischemic stroke that can be clinically useful.

Background: Vitamin K antagonist (VKA)–associated intracerebral hemorrhages (ICHs) are more likely to expand and are associated with higher mortality than primary ICH. Prompt reversal of anticoagulant effect with prothrombin complex concentrate (PCC) may promote hemostasis and decrease hematoma expansion. The aim of this study was to evaluate the impact of an electronic order set designed to standardize and facilitate more timely reversal of coagulopathy in VKA-associated ICH. Methods: We identified all adults who received PCC for VKA-associated ICH from June 2012 to June 2015 at University of California San Francisco Medical Center, which included a period before and after an electronic order set became available in 2014. We abstracted baseline demographics and clinical data from electronic health records. The primary outcome was time from radiographic identification of ICH to administration of PCC. Results: Thirty-one patients received PCC for VKA-associated ICH, including 17 patients before and 14 patients after the order set became available. Baseline demographics and clinical features were similar. Order set use was associated with a significant decrease in the time from identification of ICH on imaging to the administration of PCC (median 83 vs 45 minutes; P = .02), more accurate dosing (29.4% vs 92.9%; P < .01), and a shorter time from the PCC order to follow-up international normalized ratio (INR) testing (median 164 vs 85 minutes, P = .001). Conclusion: An electronic order set for administering PCC for VKA-associated ICH was associated with significantly faster time to PCC administration and increased dosing accuracy.

Data from randomized clinical trials have supported the safety and efficacy of intravenous tissue-type plasminogen activator (IV tPA) for acute ischemic stroke when administered within 3 hours of symptom onset, and regulatory approvals for this indication have been in place for almost 20 years. However, recent clinical trials have provided evidence that IV tPA may be safe and effective in selected patients up to 4.5 hours after symptom onset, thereby increasing the proportion of patients that may be eligible for treatment. Although professional organizations in the United States and many regulatory agencies internationally have supported this expanded time window for IV tPA, the US Food and Drug Administration has declined to approve this expanded indication and so this use of IV tPA has remained off-label in the United States. Here we review the current evidence for IV tPA in the standard and the expanded time windows and the data on current clinical practice in the United States as it relates to IV tPA treatment for acute stroke within 3 to 4.5 hours of symptom onset.

Background and Purpose: Dizziness is a frequent reason for neuroimaging and neurological consultation, but little is known about the utility of either practice. We sought to characterize the patterns and yield of neuroimaging and neurological consultation for dizziness in the emergency department (ED). Methods: We retrospectively identified consecutive adults presenting to an academic ED from 2007 to 2009, with a primary complaint of dizziness, vertigo, or imbalance. Neurologists reviewed medical records to determine clinical characteristics, whether a neuroimaging study (head computed tomography [CT] or brain magnetic resonance imaging [MRI]) or neurology consultation was obtained in the ED, and to identify relevant findings on neuroimaging studies. Two neurologists assigned a final diagnosis for the cause of dizziness. Logistic regression was used to evaluate bivariate and multivariate predictors of neuroimaging and consultation. Results: Of 907 dizzy patients (mean age 59 years; 58% women), 321 (35%) had a neuroimaging study (28% CT, 11% MRI, and 4% both) and 180 (20%) had neurological consultation. Serious neurological disease was ultimately diagnosed in 13% of patients with neuroimaging and 21% of patients with neurological consultation, compared to 5% of the overall cohort. Headache and focal neurological deficits were associated with both neuroimaging and neurological consultation, while age ≥60 years and prior stroke predicted neuroimaging but not consultation, and positional symptoms predicted consultation but not neuroimaging. Conclusion: In a tertiary care ED, neuroimaging and neurological consultation were frequently utilized to evaluate dizzy patients, and their diagnostic yield was substantial.

In the 17 years since the efficacy of intravenous tissue plasminogen activator (tPA) for acute ischemic stroke was first established, we have struggled to develop the infrastructures and systems of care that are necessary to deliver this therapy as quickly and efficiently as possible. Speed matters. Although delays in presenting to the emergency department account for most of the unrealized potential of thrombolysis, the time from when a patient arrives in the emergency department to when the tPA infusion begins—the door-to-needle time—presents a more readily accessible target for hospital-level interventions. Pooled data from 6 randomized trials and analyses of large observational data sets consistently show that faster door-to-needle times are associated with better patient outcomes. In fact, each 15-minute decrease in door-to-needle time is associated with a 5% lower odds of in-hospital mortality. Therefore, the American Heart Association: Target Stroke initiative has set a specific goal of raising the percentage of patients treated within 60 minutes from the current level of 29% to over 50%. Precisely how to actually achieve this goal involves evaluating a variety of factors, but certainly one important consideration is ensuring that appropriate staffing is available for these neurological emergencies. In this issue of The Neurohospitalist, Bhatt and Shatila examine the impact of neurohospitalists on door-to-needle times for acute ischemic stroke. The study includes data from 107 consecutive patients treated with intravenous (IV) tPA at 2 community hospitals between July 2009 and September 2011. The study was a natural experiment of sorts: halfway though the study period, coverage for acute stroke calls from the emergency department changed from a rotating schedule of 4 community neurologists with shared inpatient and outpatient responsibilities to a neurohospitalist model staffed by 2 inpatient-based neurologists. Occasional weekend coverage continued to be provided by locums tenens and community neurologists. The primary finding was that among patients treated with IV thrombolysis for stroke, 51% (24 of 47) of those evaluated by neurohospitalists were treated in 60 minutes or less, compared with 15% (9 of 60) of those evaluated by nonneurohospitalists—a difference that may be due, at least in part, to the greater likelihood that a neurohospitalists is in hospital for an emergency in-person consultation. Bhatt and Shatila are generally careful not to assert a causal relationship between a neurohospitalist’s involvement and faster door-to-needle times, with the notable exception of the article’s title. Such caution is warranted. First, there are likely to be unmeasured confounders and secular trends at play. For example, a t test comparing the mean performance of the 2 groups may obscure a secular trend of improved door-toneedle times over time. Other analytic methods such as interrupted time series analysis are often used to mitigate this possibility in other quality improvement studies. Next, relevant details on how the availability of neurohospitalists would actually impact the response time are unavailable. These details would be especially important to understand and evaluate because the acute stroke response involves interactions between